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United States Patent | 6,018,599 |
Kawai | January 25, 2000 |
When a color film original is read, a shading correction or the like is executed without using a color base film. An apparatus has: an RAM 115 in which output ratios of RGB signals from an RGB sensor (CCD) 106 for an unexposed portion of a color film have previously been stored; an amplifier 107 to amplify the signals from the CCD line sensor 106 by gains based on the RGB signal output ratios from the RAM 115 without transmitting through the base film when shading correction data is read; and a shading correction circuit 110 to give the shading correction data to an RAM 111 on the basis of outputs of the amplifier 107.
Inventors: | Kawai; Takashi (Yokohama, JP) |
Assignee: | Canon Kabushiki Kaisha (Tokyo, JP) |
Appl. No.: | 371443 |
Filed: | January 11, 1995 |
Oct 29, 1991[JP] | 3-282973 |
Current U.S. Class: | 382/274; 358/504; 358/516; 358/524 |
Intern'l Class: | H04N 001/58 |
Field of Search: | 358/500,504,515,516,518,523,524,461 382/167,162,274 |
4853768 | Aug., 1989 | Suzuki et al. | 358/517. |
4979027 | Dec., 1990 | Sakai | 358/530. |
5032903 | Jul., 1991 | Suzuki et al. | 358/75. |
5060061 | Oct., 1991 | Shisido et al. | 358/527. |
5185658 | Feb., 1993 | Itagaki et al. | 358/518. |
5237401 | Aug., 1993 | Koike et al. | 358/518. |
5414535 | May., 1995 | Kanmoto et al. | 358/504. |
Foreign Patent Documents | |||
63-124665 | May., 1988 | JP. |